Exercise training will increase the Skin Blood Flow (SkBF) responses of older men and women and the magnitude and mechanism of increase will be similar to that of young subjects. A higher SkBF at a given Critical Temperature (Tc) will reflect changes in control of SkBF exerted through the active vasodilator system. Although several exercise training studies have been performed using older subjects, none of those performed to date has examined the effects of such a training regiment on thermoregulatory function.